Laminations are used in alternating current devices such as motors and transformers in order to reduce the eddy currents in the iron core. Such laminations are thin magnetic material, and may be one-piece laminations where circular laminations are used in an electric motor. Where used in transformers, a popular form of laminations are the E and I laminations, which are interleaved to stagger the butt joints, and thus improve the magnetic properties of the core. In order to properly assembly these E and I laminations in staggered relationship, they were originally manually placed in the coil of wire, and more recently automatic lamination stack forming machines have been suggested, as in U.S. Pat. Nos. 4,073,373 for round laminations for a motor, or in 3,163,043; 3,280,453; and 3,423,814, for automatically stacking E and I laminations. Such automatic lamination stacking machines require considerable set-up time, and are usable primarily with only a single size of lamination for relatively long runs. Where short runs of transformer lamination stacks are to be assembled, it is often uneconomical to utilize the automatic lamination assembly machines.
If the manual assembly system is utilized for short runs, this has beenfound to be much too cumbersome today to feed one, two, or three laminations of each type into a stack of laminations and assemble them into a coil, since the limited dexterity of the workers limits the production output per hour and thus makes short runs relatively uneconomical.